6 Best Greenworks 40V Batteries for Lawn Mowers of 2025

This genuine Greenworks 40V 4.0Ah battery delivers rock-solid reliability and seamless integration across the brand’s expansive ecosystem of 75+ tools. With 50% more capacity than the base 2.0Ah model, it extends runtime significantly—perfect for users tackling medium to large yards without constant recharging. The built-in 4-LED fuel gauge offers precise charge visibility, eliminating guesswork, while the 1-hour rapid charge capability ensures minimal downtime between mowing sessions.

In real-world testing, the battery consistently powered a 40V cordless lawn mower through ¾ acre on a single charge, even in thick grass and uneven terrain. It maintains stable voltage output without sagging, ensuring peak performance from compatible tools like trimmers and blowers. However, while its 4.0Ah capacity is solid, it falls short of high-capacity third-party alternatives—making it less ideal for users needing marathon runtimes. Still, its optimized thermal management and consistent power delivery shine in sustained use.

Positioned as the most trusted OEM option, this Greenworks battery outperforms generic clones in longevity and system compatibility. Compared to budget 6.0Ah third-party packs, it trades raw capacity for superior firmware integration and safety protocols. It’s the ideal pick for owners prioritizing reliability, warranty support, and seamless tool communication over maximum runtime. For those already invested in the Greenworks 40V lineup, it offers peace of mind that no off-brand can match.

For budget-conscious users, the MAFACBAC 29472 40V 6.0Ah battery is a runtime game-changer, offering 50% more capacity than Greenworks’ own 4.0Ah OEM pack at less than half the price. This high-capacity lithium-ion replacement delivers extended mowing sessions, making it a compelling solution for homeowners with larger lawns who want to avoid mid-job battery swaps. Its 6.0Ah rating translates to real-world gains, especially when powering energy-hungry tools like 21-inch cordless mowers.

During testing, the battery powered a Greenworks G-MAX mower through just over an acre of mixed grass, outperforming the stock 4.0Ah battery by a wide margin. The consistent voltage output and stable discharge curve suggest quality cell construction, though the absence of a multi-LED fuel gauge means users must estimate charge levels. It charges fully in about 2.5 hours with a standard 40V charger, which is respectable for its size. However, firmware compatibility issues were noted with some tools, where the battery worked but the tool’s indicator didn’t read charge accurately.

When stacked against the genuine Greenworks 4.0Ah, this MAFACBAC model trades brand assurance for raw value and endurance. It’s best suited for users who prioritize runtime and affordability over seamless integration and long-term warranty support. While it lacks the OEM polish, it’s one of the most cost-effective ways to boost your 40V system’s productivity—especially if you’re maintaining multiple tools. For the price, it’s a no-brainer for DIYers unwilling to pay premium OEM rates.

The Qwenoer 40V 6.0Ah battery stands out with its upgraded BMS (Battery Management System) and premium A-grade 18650 cells, delivering twice the runtime of a standard 2.0Ah pack—ideal for heavy-duty lawn care. Engineered as a direct replacement for GreenWorks G-MAX tools, it offers robust safety features and real-time monitoring via an LED indicator, giving users confidence during prolonged use. This is the kind of battery that transforms cordless tools from occasional-use gadgets into serious workhorses.

In performance tests, it powered a 40V mower through over an acre of dense grass, matching or exceeding OEM runtime expectations. The integrated intelligent chip effectively prevented overheating and voltage drops, even under full load. Charging took approximately 2.5 hours, and the battery held its charge well over time. However, firmware mismatches with certain GreenWorks tools meant the charge indicator didn’t always display correctly—though the tool still ran. It’s a minor annoyance but could frustrate users expecting plug-and-play perfection.

Compared to the genuine Greenworks 4.0Ah, the Qwenoer offers double the capacity for less than half the price, making it a compelling upgrade for performance seekers. While it lacks the 3-year warranty of the OEM, its 180-day replacement policy and responsive customer support help close the gap. It’s perfect for users who want high-capacity power without breaking the bank, especially those using second-gen GreenWorks tools. For sheer runtime and safety, it delivers premium features at a mid-range price.

The Fhybat 2-pack 6.0Ah batteries redefine value for cordless lawn tool owners who hate waiting for recharges. Offering 3X the capacity of a standard 2.0Ah battery, this twin-pack setup lets users mow, trim, and blow without downtime—simply swap and go. With dual 6.0Ah units, this is the ultimate solution for large properties or multi-tool users who need uninterrupted workflow. The 4-level LED indicator and heat-dissipating design ensure both usability and longevity.

In real-world use, one battery handled an entire ¾-acre lawn with power to spare, and having a second in reserve meant zero interruptions. The snap-in design fits perfectly in GreenWorks tools, and the short-circuit and over-temperature protections provided peace of mind during extended sessions. Charging both batteries took time, but the ability to alternate between them eliminated the biggest pain point of cordless systems: downtime. The only hiccup was slightly slower charging compared to OEM, but it’s a fair trade for the added capacity.

Compared to the single OEM Greenworks 4.0Ah battery, this 2-pack delivers triple the total capacity at a lower cost per Ah. It’s not just a battery—it’s a system upgrade. For users who own multiple 40V tools or have big yards, this set offers unmatched convenience and runtime. While it lacks the brand-name assurance of Greenworks, the build quality and safety features are impressively robust—making it the best value bundle for serious homeowners.

If long runtime and dual-battery convenience are your top priorities, this 2-pack 6.0Ah set is engineered for non-stop yard work. With 240Wh of energy per battery, it powers through thick grass, wet leaves, and extended trimming with ease—making it the top pick for large lawn owners. The precise interface and onboard fuel gauge ensure smooth integration, while the surrounding exothermic holes enhance cooling during heavy use, reducing thermal throttling.

Field testing showed each battery lasting up to 80 minutes on a 40V mower, easily covering 1 acre or more depending on conditions. The dual-pack strategy eliminates downtime, letting users swap batteries while the other charges. It’s particularly effective for users with leaf blowers, mowers, and trimmers in their arsenal. However, it’s not compatible with the 21-inch MO40L02 mower, a critical limitation that could catch some buyers off guard. When compatibility is confirmed, though, performance is outstanding.

Against the genuine Greenworks 4.0Ah single battery, this 2-pack offers more than triple the total capacity and better long-term value. It’s ideal for users who need marathon sessions and hate interruptions. While it lacks Greenworks’ 3-year warranty, its compliance with CE, FCC, and RoHS standards speaks to its safety and build quality. For those seeking maximum uptime and endurance, this is the ultimate high-capacity duo—just confirm model compatibility first.

The Amitself 4.0Ah replacement hits the sweet spot between affordability and reliability, offering OEM-equivalent capacity at a fraction of the cost. With 4,000mAh of genuine lithium-ion power, it delivers the same runtime as the official Greenworks pack but for less than 40% of the price. It’s a no-frills, high-value solution for users who want dependable performance without the brand premium—perfect for budget-savvy homeowners with mid-sized yards.

In testing, it powered a 40V mower through ¾ acre of grass, matching the OEM battery’s performance. The 3-LED indicator provided a clear, if slightly less precise, readout of charge levels. It charged fully in about 2 hours, and the intelligent protection system prevented overheating and voltage spikes. While it doesn’t offer the 6.0Ah capacity of pricier alternatives, it’s perfect for users who need reliable, consistent power without overkill. It’s also fully compatible with second-gen tools, though it won’t work with older Gen 1 models.

Compared to the Greenworks 4.0Ah OEM, this Amitself pack delivers identical capacity and similar safety features at a much lower cost. It lacks the 3-year warranty, but the 12-month support and 24-hour customer service help build trust. It’s the ideal mid-range choice for users who want solid performance and savings without venturing into unproven high-capacity clones. For those upgrading a single tool, it’s one of the smartest value plays in the 40V ecosystem.